The MULT/AP test has been created and developed by Markus Christiner and Susanne Maria Reiterer and is based on previous research of its creators at the University of Vienna.

It reveals the basic phonetic aptitude to perceive unfamiliar language material and thus the potential to discriminate language differences. Apart from the general score, the ability to discriminate tone languages, stressed timed languages or syllable timed languages can be measured as well. Additionally, a questionnaire which is integrated in the test design reveals further information about other factors such as age, gender and different cognitive abilities which contribute to phonetic perception aptitude. The test has been designed for testing Europeans and North Americans as one requirement for receiving reliable results is based on the fact that those who are tested do not understand the languages used. This ensures that educational differences cannot influence the results and thus allows measuring the pure potential of phonetic aptitude perception of individuals.